Coolant problem - new(ish) owner help needed

New-ish owner here, and pretty gutted this is my first post (rather than introducing myself nicely..!), but here goes… I have a 2009 987.2 Boxster S , 60k. Bought it this summer. Been running fine, apart from having to replace the AC condensers last month due to a hole in one of them. Started it today and received a “Check coolant level” message on the dash, with the temp gauge fully to max, red light etc. Shut off the engine, and the same message/temp reading shows even before ignition, when the engine’s stone-cold. Took a look at the coolant reservoir, and noticed some white marks on the cover (uh-oh…). I noticed some white residue under the cap, and when I unscrewed it and took a look inside, there didn’t seem to be anything in there (I can see no liquid below the min level). Pretty worried by this stage, and the seems to be a bit of crud in the reservoir - this could well have been from where I unscrewed the cap. Looking for some advice on how to proceed at this stage. I’m going to assume there’s next to no coolant in there at the moment. I have some de-ionised water, and first thing I was going to do was put a litre-or-so in there and see if there’s any leak by the rear right wheel. Could it just be the cap? I read that earlier caps were problematic. This one is 987.106.044.00 (was it just the 986 / early 987’s with cap problems?). How else would coolant residue appear in the reservoir compartment? It wasn’t obvious that the cap was cross-threaded, and I’ve never opened it. O-ring looks OK as well. What else can I check? The other issue I have - if this the coolant system is pretty much empty (and I can fix whatever the issue might be), I can’t simply re-fill, right? Not least as I don't know what was in there and I don't want any mixing between different coolants. Perhaps more importantly, there might be air-locks in the system - am I looking at getting an indy / specialist to flush and re-fill? Would it be safe to fill with some deionized water, drive 1.5 miles to my nearest indy specialist and have them work on it? I can’t imagine the engine would have warmed up by then…. Thanks in advance for any advice or pointers you can give!

Unfortunately, couldn't provide images on my first post. Here are some images to go with my tale of woe!

So many threads on this topic.... My guess is that your cap has been leaking a bit - that o-ring looks a little funny, and you have no issue at all other than being a bit low on coolant because it has been evaporating and/or being spewed out. Replace the cap and find yourself some appropriate coolant. I bought the Porsche branded stuff because I didn't know better, but the major manufacturers make the right stuff - just make sure it is European spec and mentions Porsche . Add some coolant (50/50 mix if not "premixed") until you hit max. Drive it a bit and check/add as necessary. Will likely take a few times to top off. I'm assuming here you don't have coolant puddles under the car from something like a bad water pump. I had to do same when I bought my used Cayman a few years ago - once I topped it off it has used very little coolant since. I also initially panicked and took it in to the dealer - he pressure tested it and of course found nothing and sent me home.

+1. Good advise from danschy. Do it and I suspect you'll be fine. Problem most likely occurred as a result of the work you had done. Could just be air in the system working it's way out leaving you low on coolant. In my experience you don't have to be all that low to trigger the lights and temperature readings you are seeing.

Thank you both very much - still palpitating a little after the big red angry message on the dash! Online wisdom seems to be that Comma G40 is a good one to go for (and my local car-parts retail chain store sells it). If I buy it concentrated, is it OK to dilute it with deionized water? It seems harder and harder to get distilled water these days. Putting in an order now for a new cap. Meanwhile, is it worth adding some water before refilling with coolant-mix, just to check there are no leaks? It's been raining quite a lot recently (what's new in the UK?) so I can't say I've noticed any wet patches under the car. Incidentally, if I fill up to Max, surely I'll get some purged from the (hopefully closed) system once it heats up and expands? Is it not better to fill to just above min level? Again, thanks for the advice.

Since you are low, filling up to max seems prudent - the coolant should get sucked into the system. What you are filling is just the overflow tank, not directly into the cooling system. If the system were full, filling up to max may lead to some being spit out. Below is a picture I took with my engine cover removed. The blue cap towards the left side of the pic leads to the main reservoir; at the right edge is of the pic is where the filler cap your are removing is located (it is off). So you can't pour coolant directly into the system from there - just add some to be sucked in. If ambitious you could remove the engine cover and see how much is in the main reservoir and fill it up there, which is more direct, but more work.

Distilled water is readily available in grocery stores in the US. Not sure about availability on your side of the pond. Let us know how you make out.

OK, so she took 2.3L of 50:50 mix, and is now up to the MAX marker. Nothing gushing out as I filled it, so good news there. I started the engine and let it get to normal operating temperature. All seemed OK. Drove around the underground garage a little, and got out to look for any liquid. There seemed to be some coming from the front right side of the car (basically under the US-driver seat) - at about the level of the rearest point of the wheel. I'll upload some photos later, but it seemed to be coming from behind the black shielding, and I remember there were a couple of hoses that had to be drained under there if you were doing a coolant flush. It's not a huge volume of dripping, but otherwise, could it be the radiators? Any way to check that? I couldn't really see any colour to the liquid, but I've putsome paper down to catch some to get a better look. Otherwise, after a qiuck run out, there didn't seem to be any moisture or condensation around the coolant reservior, so that's a plus at least!

I doubt it is a radiator - there is a drain directly below them and they are way up front, so probably a hose. I couldn't find a picture of the routing front to back, but here is a pic of the radiator. I guess it is possible the upper hose connection is leaking down the tube towards the rear of the car, but there may be other connections along the path.

Thanks @danschy . I'm looking at your diagram, and trying to reconcile this with what I'm seeing from ground level. Now the engine's cooled down, I took a peek into the reservoir again: it looks like to lost about 100ml - I topped this back up to MAX with the 50:50 mix, but I've not run it again yet. Looking over the images I took of the underside, I can pinpoint where the drips are (though this isn't necessarily where the leak is...), based on photos from pelican parts. This is a Cayman 987 apparently (I can't imagine a Boxster 987.2 is much different in terms of the under-trays). Top of the image here is front (might be obvious to some....!): So I can match this to the image I took of the underside, with corresponding numbers. The circular area is where I see the drips. Looks reddish to me, but don't know if that's possibly rust it's picked up on the way? Embarrassingly, I'm not actually sure what the colour is of the coolant that's in there. After taking it for a drive, and then taking a look once I got back to the garage, I could see some liquid splattered onto the paint at point (4) as well: Trying to work out what could be under there at that point. The article here: Porsche Boxster Coolant Replacement / Coolant Flush - 986 / 987 (1997-08) - Pelican Parts Technical Article Check it out - Wayne explains more than you ever wanted to know about your cooling system, why you need to maintain it regularly, and how to change that pesky coolant. www.pelicanparts.com ...shows ( Figure 2 ) that the heater supply & return lines (red & purple arrows) run down that general area , but looking for a schematic to work out if they could be the culprits.

...but I think I agree - not sure it's the rad

May be unrelated but a leak in the washer fluid tank tends to show up there, at least on US cars. No idea if the tank is on the same side for right hand drive. Check and see if you're losing washer fluid and what color matches. Been a while but I recall my car taking the better part of 2 liters from new. Took a couple top ups before it stabilized.

Hey - good idea Greywolf. If it were me I'd taste the liquid - antifreeze is sweet - not sure about washer fluid but you could sample that for comparison (a small taste won't kill you!). I first witnessed that technique years ago when I coached a softball team and came back to my car and saw some liquid on the ground and was a bit concerned. One of the mothers (whose husband was a mechanic) reached down, stuck her finger in it and tasted - just AC condensation she pronounced.

I've known others who tasted fluids to determine the source including some nasty stuff like skydrol. I've always been a bit leery of it not knowing if they fix with the body and build up over time or are expelled. Washer fluid is quite bitter, astringent tasting.

I'll taste Stella or Bud but nothing stranger than that; no micro brews Didn't your mom tell you about not putting strange things in your mouth ? dnamurphy - how about taking the covers off, running the car and see where it's leaking ? Also I don't know if you are aware of it but that pin to the left of the blue cap in your engine picture is what you pull to bleed the system of air after filling it with anti-freeze hope this helps

It is either coolant or washer fluid, so both pretty benign in a small taste test. (I was surprised that when I had my colonoscopy a couple years ago I had to drink a jug of diluted Polyethylene Glycol to clean out my system!). I'm approaching 70 and have bigger health worries on the horizon than tasting some random car fluids.

More likely polypropylene glycol (AKA Propylene glycol)... it's considered harmless to the human body, and is often used as a food additive actually. " Propylene glycol is considerably less toxic than ethylene glycol and may be labeled as "non-toxic antifreeze ". It is used as antifreeze where ethylene glycol would be inappropriate, such as in food-processing systems or in water pipes in homes where incidental ingestion may be possible." And at times it's been sold as automotive antifreeze. Only issue with it - it's slightly more expensive than ethylene glycol. Typical concentrations used as a coolant - down to -50F, 40% poly/60% water. You can find it at most marine hardware suppliers and RV suppliers. It's frequently used to fill fresh-water systems in boats and RV's when they're going to be stored for a winter. It's non-toxic properties make it quite attractive for this purpose. More than you ever wanted to know... (I used to use it as a solvent/circulation fluid in pumped dye-lasers, and on my sailboat, so I got familiar with it..)

BTW - a safer test for antifreeze - ethylene glycol feels slightly "slick" if rubbed between your fingers. Once you feel it - it's easy to distinguish between it and washer fluid (which contains methanol, and will not have the slick feeling.)

[Image-only or quote-only post; no author-written text.]

There have been a couple of posts on this message, and it happened to me. My understanding is that if the cooling fluid level gets too low, you get the message and just to scare the crap out of you to get your attention, the water temp gauge pegs out. It does not mean that the cooling fluid has gotten that hot. If the pink cooling fluid is dripping from the pan at about the level of the seats, you could pull the pan off and see if there is a leak where a coolant fluid hose connects to a coolant manifold coming off the engine. It could be a bad o-ring at that connection rather than the hose which then leads forward to coolant tubes.[/

Gee where have I heard that before ?? Oh I know - it was me 3 days ago Also why wouldn't you do this on day one instead of speculating about what color it is or how it tastes ; duh Sorry not to pick on you but so many posts on P9 go on and on about what, where, how and never take anything apart to actually see what's going on Maybe we don't have tools; if you own a Porsche you can afford a $100 set of Husky or whoever's tools kit. No lift - get a floor jack and 4 jack stands; another $100 Am I just an old grump or does that make sense ?